Lubricating oil



Patented May 16, 1939 PATENT FFECE 2,158,389 LUBRICATING on.

Charles Cole Towne,

The Texas Company, poration of Delaware Beacon, N. Y., assignor to NewYork, N.'Y., a cor- No Drawing. Application April 30, 1936 Serial No.17,149

'1 Claims.

This invention relates to the manufacture of an improved lubricating oilcharacterized by an increased viscosity index and other desirableproperties.

The invention contemplates the preparation of mineral lubricating oilhaving an increased viscosity index by the addition to the oil of aminor proportion of the raflinate from an extraction with a waxanti-solvent of blown or polymerized fatty oils, such as blown rapeseedoil and polymerized fatty drying oils.

In the production of high grade lubricating oils, it is well known thata relatively small change in the viscosity of the oil betweentemperatures of say 100 F. and 210 F. is desirable. In other words, itis advantageous for the oil to have a relatively flat viscositytemperature curve, which means that the oil has a high viscosity indexas defined by Dean and Davis in their article 0 in Chemical andMetallurgical Engineering, vol.

36, page 618.

It has heretofore been proposed to add blown rapeseed oil or polymerizedfatty oils to lubricating oil. However, the addition of substantialproportions of such oxidized or polymerized fatty oils is objectionablefor high grade lubricants, such as motor oils, due to the increase insludging characteristics, lack of oxidation stability and increasedcarbon residue. I have discovered that 0 this objection can be overcomeand a superior product for this purpose obtained by extracting theoxidized or polymerized fatty oils with a solvent of the class of waxantisolvents, and then employing the solvent insoluble portion orrainnate as the viscosity index improving material for the lubricatingoil. The materially increased effectiveness of the raffinateportion'over the original oxidized or polymerized oil enables a muchsmaller proportion to be used to obtain the same effect, and thecompounded oil possesses increased stability. Very satisfactory resultshave been secured by extracting blown rapeseed oil or polymerized fattydrying oils, such as perilla, soy bean, and p ppy seed, with a solventsuch as acetone, or certain alcohols such as the propyl alcohols and thebutyl alcohols. The extract or soluble portion contains material ofcomparatively small efiectiveness in increasing the viscosity index ofthe lubricating 0'1, and in addition objectionable constituents whichincrease the sludging tendency or oxidation instability of the oil arefound in this extract. The insoluble portion or rafiinate, on the otherhand, constitutes the desirable material of high effectiveness forincreas- 65 ing viscosity-ind and also imparts other desirable qualitiessuch as increasing oiliness and film strength of the lubricant. Theraflinate, after stripping of the retailed solvent, is added in a minorproportion to the'mineral lubricating oil, generally in a proportion ofabout 1 to 10% on the weight of the oil. The raflinate may be addeddirectly to the lubricating oil, or a solution of the raflinate in anaromatic solvent, such as benzol, may be prepared and added to the oiland the solvent removed by stripping.

By way of example, rapeseed oil was blown at elevated temperatures inthe customary manner to a viscosity at 210 F. of 1785. 56 g. of thisblown rapeseed oil were shaken vigorously with 800 cc. of acetone andallowed to settle. The lower insoluble layer was drawn off and heatec'to drive off the retained acetone. The uppe1 .layer was also heated todrive off the solvent thereby recovering the oil extracted by the acetone. 22 g. of oily material insoluble in acetom constituting 39%rafllnate were obtained, a against 34 g. extracted by acetone equivalentt 61% extract.

The following resultswere. obtained upon th addition of the indicatedpercentages of the ace tone insoluble portion or rafilnate and theaceton soluble portion or extract to a naphthene bar oil:

Viscosity, T.

210 Zero A. B.

T.chart 200 pale oil 216 43 35000 Same+5% acetone extract of blownrapeseed 241 46 30000 Serne+2% acetone rafiinate oi blown rapeseed 25747.5 27000 Same+5% acetone rafiinate of blown rapeseed 341 55.5 20000 5%of the rafllnate increas 100 points as against an i crease of 51 pointsfor the extract, while the st bility of the oil bl ded with the ramnatev considerably improved over that blended with-1 extract. Moreover, 2%of the rafilnate was ion to give a greater increase in viscosity indextt 5% of the extract.

Similar results are obtained by extract polymerized fatty drying oilswith acetone or alcohols mentioned, and employing the raflin orinsoluble portion as viscosity index improi for lubricating oils. Thefatty drying oils polymerized or bodied in the customary man by heatingin an open kettle until they becc It is thus seen that the viscosityindex viscous as is well understood in the paint and varnish making art.

The following results show a comparison of the rafilnate or insolubleportion of the oxidized or polymerized oils with the originalpolymerized or blown oils themselves, when added to various minerallubricating oils:

Viscosity, F.

Zero, V. I. 100 210 A S. T. M

chart 500 pale oil 530 52. 5 350, 000 3ame+5% blown rapeseed 628 60 250,000 46 3ame+2% acetone insoluble portion of blown re d 638 80 275, 00043 ame+5% polymerized perilla oil 615 58. 5 300, 000 36 ;ame+5% acetoneinsoluble portion of polymerized perilla oil 704 63 225, 000 49 a1ne+5%polymerized soy been oil 595 57 300, 000 28 lmne+5% acetone insolubleportion of polymerized soy been 011 643 59. 5 325, 000 38 lame+5%polymerized poppy seed oil- 643 59 325, 000 33 ame+5% acetone insolublepornon of polymerized poppy seed oil 708 03 225, 000 48 )0 pale oil 31046 120,000 8. 5 ame+5% acetone insoluble portion of blown rapeseed oil478 60 70,000 85 ame+2% acetone insoluble portion of blown rapeseed oil373 51 90, 000 46 i0 pale oil 771 59. 0 700, 000 2 a'me+5% acetoneinsoluble porlion oi blown rapeseed oil 1, 110 79. 5 525, 000 61 ame+2%acetone insoluble portion of blown rapeseed oil 884 67 550, 000 38Obviously many modifications and variations f the invention, ashereinbefore set forth, may a made without departing from the spirit and:ope thereof, and therefore only such limitaons should be imposed as areindicated in the amended claims.

I claim:

1. A lubricating oil of improved character com- 'ising a minerallubricating oil containing a inor proportion of the ramnate obtainedfrom .e extraction of a fatty oil selected from the cup consisting ofblown and polymerized fatty is with a. solvent selected from the groupcon- :ting of acetone, propyl alcohols and butyl alhols.

aieaeeo 2. A lubricating oil of improved character comprising a minerallubricating oil containing, to

. the extent of around 1' to the constituents 4. The method ofmanufacturing an improved lubricating oil which comprises incorporatingin mineral lubricating oil, to the extent of around 1 to 10%, theconstituents of an oil selected from the group consisting of blown andpolymerized fatty oils and which are substantially insoluble in anextraction solvent selected from the group consisting of acetone, propylalcohols, and butyl alcohols and which are characterized by highviscosity index as well as resistance to oxidation and sludging.

5. A lubricating oil of improved character comprising a minerallubricating oil containing 1 to 10% of the rafiinate from an extractionof blown rapeseed ofl with a solvent selecteclfrom the group consistingof acetone, propyl alcohols and butyl alcohols.

6. A lubricating oil of improved character comprising a minerallubricating oil containing 1 to 10% of the rafilnate from an extractionof polymerized perilla oil with a solvent selected from the groupconsisting of acetone, propyl alcohols and butyl alcohols.

7. A lubricating oil of improved character comprising a minerallubricating oil containing 1 to 10% polymerized poppy seed oil with asolvent selected from the group consisting of acetone, propyl alcoholsand butyl alcohols.

CHARLES COLE TOWNE.

of the railinate from an extraction of

